In conventional image recognizing devices, various sensors such as a camera are used to obtain a scene including a target, being an object to be recognized, as image information, and target recognition is conducted based on the image information and fragmentary knowledge with respect to the target. The main object of the target recognition is to grasp the scene including the target from the image information as accurately as possible, and rebuild the target. At this time, as a method for specifying the target, a template matching method is frequently used, which obtains a consistency between the target in the image information, and many templates prepared beforehand with respect to the target.
In such a conventional target recognizing device however, it is necessary to prepare many templates so that consistency with various targets can be realized, in order to correspond to various conditions. In other words, there is a problem in that before conducting the recognition processing, it is necessary to store the templates for the number of types of target, being an object to be recognized, beforehand in the target recognizing device.
When it is attempted to realize the development of an autonomously movable robot having a device which recognizes a scene including a target, and an autonomously shift device, with a conventional technique, the following method can be considered. That is to say, at first, a plurality of image information relating to a target point is stored beforehand as templates. Image information including the target point is then obtained by a camera or the like mounted therein, to extract an area having the best consistency with the template stored in advance, from the image information. The robot then moves toward the direction corresponding to the extracted area, by the autonomously shift device.
In dynamic scene analysis for analyzing the movement of a target object, by using a plurality of images continuous timewise, an optical flow is frequently used. The optical flow is a vector representation of the direction of movement at one point on the image and the magnitude of the velocity thereof. By measuring the optical flow of the target object, the movement of the target object can be recognized.
In the target recognizing device in the autonomously movable robot however, the scene photographed by a camera or the like changes moment by moment due to the movement of the robot, and even in the case of the same target, the size of the target occupying the obtained image information changes. Therefore, even by simply using the optical flow, it is difficult to perform accurate target recognition, and many templates corresponding to the respective situations become necessary.
As described above, in the conventional technique, there is a problem in that it may be difficult to perform accurate recognition processing of a target in a scene, which is changing timewise.